62 DIFFERENT EFFECT OF TRICHOSTATIN A ON IN VITRO DEVELOPMENT OF PORCINE TRANSGENIC SOMATIC CELL NUCLEAR TRANSFER AND PARTHENOGENETICALLY ACTIVATED EMBRYOS

2008 ◽  
Vol 20 (1) ◽  
pp. 112 ◽  
Author(s):  
H. X. Wei ◽  
K. Zhang ◽  
Y. F. Ma ◽  
Y. Li ◽  
Q. Y. Li ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Trichostatin A ◽  
Polar Body ◽  
Cell Number ◽  
Cell Numbers ◽  
First Polar Body ◽  
Electrical Fusion

Accumulating evidence suggests that trichostatin A (TSA), a histone deacetylase inhibitor, can increase the success rate of somatic cloning. The objective of this study was to investigate the effect of 50 nm TSA treatment on the development of porcine somatic cell nuclear transfer (SCNT) and parthenogenically activated (PA) embryos. Cumulus-oocyte complexes were matured in vitro. The oocytes with the first polar body (PB1) were chosen for SCNT, and the rest with PB1 or good morphology were selected for PA by a single 100-μs direct current pulse of 1.6 kV cm–1, the same parameter as for electrical fusion. GFP transgenic fetal fibroblast cells were used as nuclear donors. Data were analyzed using SPSS (13.0; SPSS, Inc., Chicago, IL, USA) with one-way ANOVA. In Experiment 1, immediately after electrical fusion and activation, the reconstructed embryos were randomly cultured in porcine zygote medium 3 (PZM3) with 10 μg mL–1 cytochalasin B (CB) and 10 μg mL–1 cycloheximide (CHX), with either 0 nm (control) or 50 nm TSA for the first 4 h, before being cultured for another 20 h in PZM3 without CB and CHX. After being washed, the embryos were cultured in PZM3 medium without TSA until Day 6 at 39.0°C, 5% CO2, 5%O2, 90% N2, and 100% humidity. The same experimental design was used for PA embryos concurrently. The results showed that there were no significant differences in blastocyst rates for SCNT or PA between control and TSA groups (23.0 ± 6.1% v. 27.9 ± 6.3%; 21.0 ± 1.0% v. 17.5 ± 3.2%, respectively). Neither were there differences in the cell numbers of blastocysts (38.3 ± 5.7 v. 32.2 ± 3.4; 42.2 ± 3.5 v. 39.0 ± 1.9, respectively). In Experiment 2, TSA treatment was prolonged to either 36 or 40 h. The blastocyst rates of SCNT were increased (7.3 ± 1.2% (0 h), 13.3 ± 2.6% (36 h), and 20.0 ± 3.3% (40 h)), whereas those of PA were decreased (46.7 ± 5.0% (0 h), 27.7 ± 6.5% (36 h), and 30.8 ± 6.3% (40 h)). The cell numbers of blastocysts from either SCNT or PA were also decreased (SCNT: 47.5 ± 3.8, 37.5 ± 2.0, and 37.1 ± 3.3; PA: 46.1 ± 1.9, 37.5 ± 1.9, and 39.3 ± 2.2; P < 0.05). In Experiment 3, the cell number and the apoptotic index of Day 5, 6, and 7 PA blastocysts treated with 0 or 50 nm TSA were determined by the terminal deoxynucleotide-mediated nick end labeling (TUNEL) assay (Table 1). The results suggested that TSA treatment probably delayed embryo development, which may be one of the reasons for the lower cell numbers in the TSA-treated group. Table 1. Cell apoptosis of PA blastocyst by TUNEL

scholarly journals 56 SOMATIC CELL NUCLEAR TRANSFER IN NON-HUMAN PRIMATES: THE POSSIBILITY OF USING OOCYTES MATURED IN VITRO FOR UP TO 3 DAYS AS HOST OOPLASTS

2005 ◽  
Vol 17 (2) ◽  
pp. 177
Author(s):  
N.T. Uoc ◽  
B.D. Bavister ◽  
N.V. Hanh ◽  
L.C. Bui ◽  
N.T. Thanh ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Polar Body ◽  
Reproductive Technologies ◽  
High Dose ◽  
Cumulus Expansion ◽  
First Polar Body

Production of cloned nonhuman primate embryos has been reported using mature oocytes obtained from donors treated in vivo with a high dose of recombinant human FSH (r-hFSH, 35 IU per day for 10 days). The disadvantages of this approach are the high cost of hormones and the need to use the oocytes shortly after collection. Our study aimed to investigate the possibility of using initial in vivo treatment with a reduced FSH dose followed by in vitro culture for long periods of up to 3 days to produce mature monkey oocytes as host ooplasts for somatic cell nuclear transfer (SCNT). Adult female long-tailed Macaque (Macaca fascicularis) monkeys were treated with r-hFSH (Serono, Aubonne, Switzerland, 35 IU per day, i.m.) either for 10 days with an injection of hCG (1000 IU, i/m) 34 h before oocyte collection (G.I) or with only r-hFSH for 7 days (G.II). Cumulus oocyte complexes (COCs) were collected by follicular aspiration and then cultured in TCM-199 medium (GIBCO) supplemented with estradiol-17β, FSH, LH, and 10% FCS at 39°C in an incubator with 5% CO2 in air. The maturation rate based on the level of cumulus expansion and the presence of the first polar body was recorded at the moment of collection and during 24 h, 48 h, and 72 h of in vitro maturation (IVM). For SCNT, the mature Metaphase II oocytes were separated from cumulus cells and selected for enucleation in the presence of cytochalasin B (Sigma, St. Louis, MO, USA). Skin fibroblasts obtained from adult monkeys were cultured in DMEM+ 10% FCS and induced to quiescence in DMEM 0% FCS 2 days before use. A single cell was transferred under the zona of each enucleated oocyte. Couplets were fused with two direct current (DC) pulses of 220 V/mm for 25 μs in Zimmerman medium. Fused oocytes were cultured in medium containing cyclohexamide for 6 h before placing them into monkey culture medium (Cook, Brisbane, Australia). The average number of oocytes collected per animal were 21.2 (n = 18) and 18.6 (n = 12) for the G.I and G.II treatments, respectively. For G.I, the rate of COCs with fully expanded cumulus was 42% at collection and was maximal (80%) at Day 1 of IVM. For G.II, fully expanded cumulus was not observed at the time of collection and during the first 2 days of IVM, but 75% of COCs had full cumulus expansion by Day 3 of IVM. The rates of intact and fused oocytes were 50.3% for G.I and 55.4% for G.II. From the fused oocytes, 67.8% and 64.4% developed to the 4- to 8-cell stages at Days 2–3 after nuclear transfer for G.I and G.II, respectively. From these data, it can be concluded that this approach can be applied to optimize production of mature oocytes for non-human primate SCNT and ART (assisted reproductive technologies) programs. This work was supported by AIRE-Development.

45 EFFECT OF TRICHOSTATIN A TREATMENT ON THE TERM DEVELOPMENT OF SOMATIC CELL NUCLEAR TRANSFER RABBIT EMBRYOS

2008 ◽  
Vol 20 (1) ◽  
pp. 103 ◽  
Author(s):  
Q. Meng ◽  
Z. Polgar ◽  
J. Liu ◽  
A. Dinnyes
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Trichostatin A ◽  
Cumulus Cell ◽  
Cell Number ◽  
Pregnant Female ◽  
Rabbit Embryos

The efficiency of somatic cell nuclear transfer (SCNT) is low in the rabbit. So far, there have been few live births reported and most clones died within the first 3 weeks after birth. It has been shown that treatment with trichostatin A (TSA), a histone deacetylase inhibitor, improved cloning efficiency in cattle (Enright et al. 2003 Biol. Reprod. 69, 896–901) and mice (Kishigami et al. 2006 Biochem. Biophys. Res. Commun. 340, 183–189; Rybouchkin et al. 2006 Biol. Reprod. 74, 1083–1089). Although a recent report indicated that TSA treatment could increase the cell number of rabbit SCNT blastocysts (Xu et al. 2007 Reprod. Fertil. Dev. 19, 165), term development of TSA-treated cloned embryos in this species has not been reported. In this study we investigated the effect of TSA treatment on the term development of somatic cell nuclear transfer (SCNT) rabbit embryos. The oocytes and cumulus cells were collected from superovulated Hycole hybrid rabbits. After staining with Hoechst 33342 and locating following 1–2 s of UV illumination, the nuclei of oocytes were removed by micromanipulation, A cumulus cell was then inserted into the perivitelline space and fused with the cytoplast with three 20 μs 3.2 kV cm–1 DC pulses. Fused embryos were activated using the same electrical parameters 1 h later, treated with 2 mm 6-dimethylaminopurine and 5 μg mL–1 cycloheximide for 1 h, and then subsequently cultured in Earles Balanced Salt Solution (EBSS) with or without 5 nm TSA for 10 h. The embryos were then cultured in EBSS either overnight (before ET) or for 4.5 days. Embryos were transferred at the 2- to 4-cell stages to the recipients 22 h after collection of the oocytes from the donors. Caesarean sections were performed on Day 30 post-ET. In vitro developmental data (Table 1) showed no differences in the cleavage, blastocyst rates, and blastocyst cell numbers between the TSA-treated or untreated cloned embryos. After ET in the TSA group, one pregnant female delivered 7 live and 3 stillborn pups, but all of the live pups died within 1 h to 19 days later. In the untreated group, one pregnant female gave birth to 2 live and 1 stillborn pup. One pup died within 1 h after birth; the other survived (2.5 months old when this abstract was submitted). In conclusion, the results indicate that TSA treatment has a limited effect on in vitro development of SCNT embryos, and both TSA-treated and untreated SCNT clones can develop to term in rabbit. The effects of TSA treatment on the health of clones need further investigation. Table 1. In vitro and in vivo development of SCNT rabbit embryos with or without TSA treatment This study was supported by Wellcome Trust (Grant No. 070246), EU FP6 (MEXT-CT-2003-509582, MRTN-CT-2006-035468), and Chinese-Hungarian Bilateral projects (TET CHN-28/04, CHN-41/05).

37 EFFECTS OF TRICHOSTATIN A TREATMENT ON BOVINE SOMATIC CELL NUCLEAR TRANSFER EMBRYOS

2008 ◽  
Vol 20 (1) ◽  
pp. 99 ◽  
Author(s):  
A. E. Iager ◽  
Z. Beyhan ◽  
P. J. Ross ◽  
N. P. Ragina ◽  
K. Cunniff ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Trichostatin A ◽  
Cell Number ◽  
Total Cell ◽  
Preimplantation Embryos ◽  
Total Cell Number ◽  
Treatment Groups

Faulty epigenetic reprogramming is a likely major cause of the low success rate observed in all mammals produced through somatic cell nuclear transfer (SCNT). It has been reported that treatment of reconstructed mouse embryos with the potent histone deacetylase inhibitor, trichostatin A (TSA), results in significantly increased developmental capacity of SCNT preimplantation embryos and live offspring (Kishigami et al. 2006 Biochem. Biophys. Res. Commun. 240, 183–189; Rybouchkin et al. 2006 Biol. Reprod. 74, 1083–1089; Kishigami et al. 2006 J. Reprod. Dev. 53, 165–170). Studies investigating similar reprogramming capabilities of TSA in bovine SCNT embryos report conflicting results (Akagi et al. 2007 Reprod. Fertil. Dev. 19, 24 abst; Iwamoto et al. 2007 Reprod. Fertil. Dev. 19, 48 abst). In this study, the effects of TSA treatment on in vitro development of bovine SCNT embryos were examined. Bovine fetal fibroblasts were cultured under contact inhibition for 2 to 5 days and used as donor cells for SCNT. Oocytes were aspirated from abattoir-derived ovaries, and matured in vitro for 18 h prior to enucleation. Reconstructed SCNT couplets were electrofused, and then activated 24 h post-maturation using 5 µm ionomycin followed by 2 mm dimethylaminopurine (DMAP) for 4 h. SCNT embryos were subjected to 0 (control; C-NT) or 50 nm TSA for 13 h post-ionomycin (hpi) TSAa-NT) or 13 hpi + 6 h starting from 40 hpi (TSAb-NT). IVF embryos were produced as an additional control. All embryos were cultured in KSOM supplemented with 3 mg mL–1 BSA for 7.5 days, with 5% FBS added on Day 3. Experiments were repeated 3 or 7 times, and data were analyzed a -way ANOVA procedure. Developmental rates to the blastocyst stage and total cell number of blastocysts were determined. Total cell numbers were determined by fixing blastocysts in 4% paraformaldehyde, and staining with bisbenzimide 33342, followed by microslide mounting and visualization using an epifluorescence microscope. No difference was observed in cleavage rates among the four treatment groups, C-NT, TSAa-NT, TSAb-NT, and IVF, with the rates being 66%, 75%, 73.1%, and 82.3%, respectively (P = 0.33); nor was any improvement seen in the rate of blastocyst development of TSAa-NT or TSAb-NT over C-NT embryos: 36%, 40.2%, and 30.2%, respectively (P = 0.22). Furthermore, there was no significant difference in mean total cell number of blastocysts among treatment groups: C-NT, 120.2; TSAa-NT, 124.2; TSAb-NT, 129.3; and IVF, 141.1 (P = 0.29). These results suggest that 50 nm TSA treatment immediately following activation does not affect the development of bovine SCNT preimplantation embryos.

356 IMPROVED ENUCLEATION EFFICIENCY FOR PIG SOMATIC CELL NUCLEAR TRANSFER BY DENUDING OOCYTES AT 30 HOURS OF IN VITRO MATURATION

2007 ◽  
Vol 19 (1) ◽  
pp. 293 ◽  
Author(s):  
K. Song ◽  
J. Park ◽  
E. Lee
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Polar Body ◽  
Digital Camera ◽  
Cumulus Cells ◽  
Cell Number ◽  
Blastocyst Formation ◽  
Significant Difference

Oocytes for somatic cell nuclear transfer (SCNT) have to be removed from their cumulus cells before enucleation. Denuding oocytes by vortexing or repeated pipetting makes the polar body (PB) deviate from the metaphase (MII) plate, which in turn makes it difficult to remove DNA materials completely during enucleation. We hypothesized that denuding oocytes at 30 h of IVM maintains the MII plate and PB in a closer position and therefore makes it easy to enucleate. To test this hypothesis, oocytes were matured in TCM-199 supplemented follicular fluid, hormones, EGF, cysteine, and insulin for first 22 h, and in a hormone-free medium for 18 h with three modifications: (1) cumulus cells were removed from oocytes just prior to enucleation at 40 h of IVM (control), (2) oocytes were denuded at 30 h of IVM and co-cultured with their detached cumulus cells for 10 h (D+), and (3) oocytes denuded at 30 h of IVM were cultured without cumulus cells (D-). After IVM, some oocytes were stained with Hoechst 33342 and photographed by a digital camera; the distance between the MII plate and the PB were measured using an image analysis program (ImageJ 1.36; http://rsb.info.nih.gov/ij). Also, the enucleation rate after blind enucleation and the in vitro development of SCNT embryos were determined. For SCNT, oocytes were enucleated, and nuclear material from donor cells (skin fibroblasts from a miniature pig) was inserted; oocytes were then electrically fused, and activated 1 h after fusion. SCNT embryos were cultured in a modified NCSU-23 (Park et al. 2005 Zygote 13, 269-275) for 6 days. Embryos were examined for their cleavage and blastocyst formation on Days 2 and 6, respectively (the day of SCNT was designated Day 0). Data were analyzed by the GLM procedure and the least significant difference test in SAS (SAS Institute, Cary, NC, USA). The distance between the MII plate and the PB was significantly (P &lt; 0.01) shorter in D+ and D- embryos (19.4 and 18.9 �m, respectively) than in the controls (25.5 �m). Enucleation rates after blind enucleation were significantly (P &lt; 0.01) higher in D+ and D- groups (77% and 72%, respectively) than in the controls (60%). Oocyte maturation (89–91%), SCNT embryo cleavage (71–77%), blastocyst formation (4–5%), and embryo cell number (39-45 cells/embryo) were not altered by different denuding methods. The perivitelline space (PVS) increases with time during maturation and denudation, after PB extrusion markedly enhances PB deviation. It is likely that increased PVS in control oocytes enhanced PB deviation during denudation and then resulted in lower enucleation rate. In conclusion, the results of this study indicated that denuding at 30 h of IVM maintained the MII plate and the PB in a closer position and improved enucleation efficiency without impairing developmental capacity of SCNT embryos. This work was supported by the Research Project on the Production of Bio-organs (No. 200506020601), Ministry of Agriculture and Forestry, Republic of Korea.

100 EFFECT OF DIFFERENT POST-ACTIVATION TREATMENTS ON THE DEVELOPMENT OF SOMATIC CELL NUCLEAR TRANSFER PIG EMBRYOS

2007 ◽  
Vol 19 (1) ◽  
pp. 167
Author(s):  
H. Y. Yong ◽  
K. Song ◽  
E. Lee
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Polar Body ◽  
Donor Cell ◽  
Cell Number ◽  
Donor Nucleus ◽  
Gamma Tubulin ◽  
Stock Solutions

Activation treatment is one of the important factors that affect the development of somatic cell nuclear transfer (SCNT) embryos. We examined the effect of post-activation (PA) treatment on the change in donor nucleus and SCNT embryo development in pig. Cumulus–oocyte complexes (COCs) were matured in TCM-199 supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones for the first 22 h and in fresh hormone-free medium for 18 h. After 40 h of IVM, oocytes with a polar body were enucleated, injected with a donor cell (ear skin fibroblasts bearing the human decay accelerating factor gene), electrically fused, and activated 1 h after fusion. Then, SCNT embryos were cultured in a modified NCSU-23 medium (Park et al. 2005 Zygote 13, 269–275) containing no additives (control), 5 �g mL-1 cytochalasin B (CB), 0.4 �g mL-1 demecolcine (D), or CB+D for 4 h. CB and D were prepared from stock solutions of 5 mg mL-1 CB in DMSO and 10 �g mL-1 D in Hank&apos;s balanced salt solution (HBSS), respectively. After PA treatment, SCNT embryos were cultured in a modified NCSU-23 medium for 6 days. The embryos (n &equals; 188, 189, 187, and 186 for control, CB, D, and CB&plus;D, respectively) were examined for cleavage and blastocyst (BL) formation on Days 2 and 6, respectively (Day 0 &equals; the day of SCNT). Cell number of BL was examined by counting the number of nuclei stained with Hoechst 33342 under fluorescence. To assess the nuclear structure, some of the fused oocytes were fixed at 12 h after PA and stained with aceto-orcein (n &equals; 42, 44, 43, and 45 for control, CB, D, and CB&plus;D, respectively). Nuclear state was classified as 1 pseudopronucleus (PPN), multi-PPN, and others. Data were analyzed by ANOVA (GLM procedure) in SAS (SAS Institute, Inc., Cary, NC, USA). PA treatment with D and CB&plus;D significantly (P &lt; 0.05) increased 1 PPN formation (84 and 80&percnt;, respectively) compared to control and CB (62 and 64&percnt;, respectively). Conversely, a higher (P &lt; 0.001) rate of multi-PPN was observed in control and CB (31 and 36&percnt;, respectively) than in D and CB&plus;D (9 and 7&percnt;, respectively). This result was in contrast with the finding in mouse that nocodazole, another microtubule depolymerizing agent, induced multi-PPN in reconstructed zygotes. Pig meiotic spindles differ at their poles from those in mice by lacking &gamma;-tubulin. Absence of &gamma;-tubulin in pig oocytes would make spindle dynamics more sensitive to depolymerization, which might lead to a different result in this study. Embryo cleavage (77&ndash;85&percnt;) was not altered by PA treatments, but BL formation was significantly (P &lt; 0.05) increased by CB, D, or CB&plus;D (26, 28, and 28&percnt;, respectively) compared to control (16&percnt;). Total cell number of BL (36&ndash;40 cells/BL) was not different among groups. These results indicate that PA treatment with CB and/or D improved in vitro development of SCNT pig embryos and that D treatment effectively prevented the formation of multi-PPN. This work was supported by the Research Project on the Production of Bio-organs (No. 200506020601), Ministry of Agriculture and Forestry, Republic of Korea.

46 EFFECT OF SHORT-TERM TRICHOSTATIN A TREATMENT ON BOVINE SOMATIC CELL NUCLEAR TRANSFER EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 123
Author(s):  
H. J. Oh ◽  
J. E. Park ◽  
M. J. Kim ◽  
S. G. Hong ◽  
J. T. Kang ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Trichostatin A ◽  
Cell Number ◽  
Total Cell ◽  
Developmental Competence ◽  
Short Term ◽  
Total Cell Number

Epigenetic reprogramming such as acetylation in somatic cell nuclear transfer (SCNT) has been known as one of problems in cloned embryos. For resolving this acetylation reprogramming, many investigators recently have reported the effect of long-term culture of post-activated SCNT embryos using trichostatin A (TSA), a histone deacetylase inhibitor (HDACi). The objective of this study is to investigate the effect of short-term TSA treatment on in vitro developmental ability and the quality of bovine SCNT embryos. Immature oocytes were aspirated from abattoir-derived ovaries, matured in vitro for 22 h, and enucleated. A bovine fetal fibroblast was placed into the enucleated oocyte and fused by electrical stimulation. The fused couplets were activated by 4-min incubation in 10 μm ionomycin, followed by 4 h of culture in 1.9 mm 6-dimethylaminopurine with or without TSA (0, 50, or 100 nm). The SCNT embryos were subsequently cultured in modified synthetic oviduct fluid medium for 8 days. Developmental competence was assessed by blastocyst formation and total cell number. Total cell numbers were determined by staining with bisbenzimide 33342. As results, developmental competence to blastocysts was higher in 100 nm than control (36.7 v. 27.9%, P < 0.05). In blastocyst hatching rate, TSA 100 nm group (19.5%) at 8 days showed an increased pattern as opposed to control and TSA 50 nm group (11.1 and 12.7%; P < 0.05). No significant differences in two cell and morula stage were observed among treatment groups. In terms of development to hatching stage of blastocysts, TSA 100 nm group (19.5%) at 8 days has a significant effect compared to control and TSA 50 nm group (11.1 and 12.7%; P < 0.05). Total cell number of blastocysts derived from TSA 100 nm was significantly higher (P < 0.05) than that in TSA 50 nm (116 v. 100), whereas there was not significant difference between control and TSA 100 nm. In conclusion, short-term culture with high concentration of TSA improved the blastocysts formation however total cell number of blastocysts showed contradictory result. The epigenetic modification by TSA treatment on bovine SCNT needs further investigation. This study was financially supported by KOSEF (grant # M10625030005-08N250300510) and the Korean MEST, through the BK21 program for Veterinary Science.

185 DEVELOPMENT CAPACITY OF PRE- AND POSTPUBERTAL PIG OOCYTES EVALUATED BY SOMATIC CELL NUCLEAR TRANSFER AND PARTHENOGENETIC ACTIVATION

2013 ◽  
Vol 25 (1) ◽  
pp. 241 ◽  
Author(s):  
H. S. Pedersen ◽  
R. Li ◽  
Y. Liu ◽  
P. Løvendahl ◽  
P. Holm ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Cell Number ◽  
Time Interval ◽  
Cell Stage ◽  
Parthenogenetic Activation ◽  
Development Capacity ◽  
Developmental Capacity

Most of the porcine oocytes used for in vitro studies are collected from gilts. Our aims were to study development capacity of gilt v. sow oocytes (pre- and postpubertal respectively) using 2 techniques illustrating development competence [parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT)], and to describe a simple method to select the most competent oocytes. Inside-ZP diameter of in vitro-matured gilt oocytes was measured (µm; small ≤110; medium >110; large ≥120). Gilt and sow oocytes were morphologically grouped as good (even cytoplasm, smooth cell membrane, visible perivitelline space) or bad before used for PA (good and bad) or SCNT (good). The PA and SCNT were performed as before with minor modifications (Cryobiol. 64, 60; Cell. Reprogr. 13, 521) before culture for 6 days in a standard or timelapse incubator. Rates of cleavage (CL%, Day 2), blastocyst (BL%, Day 6), and blastocyst cell number (Hoechst 33342) were recorded. For PA embryos in a timelapse incubator (26 oocytes/group; 2 replicates), the first appearance of 2-cell stage was recorded. Between groups, CL% and BL% were analysed by chi-square and cell number by t-test. Results are presented in the table for the development of good oocytes after PA. The results show a low CL% of small-gilts compared with the other groups. The BL% increased with gilt-oocyte-diameter; however, sow oocytes reached the highest BL%. Total cell number was higher in sow than in gilt blastocysts. The SCNT experiments showed no differences in CL% (90–96) and blastocyst cell number (51–59) between groups. The BL% was higher in medium gilts and sows (41; 45) compared with large gilts (21). The BL% of bad oocytes was 1% from all 4 groups (176 oocytes, 25 replicates). Time interval for appearance of 2-cell stage for embryos developing into blastocysts showed no differences between groups (19–20 h). Within groups, this time interval showed a larger standard deviation for embryos not developing v. embryos developing into blastocysts. It is concluded that (a) sow oocytes have higher developmental capacity compared to gilts, (b) small gilt oocytes are not developmentally competent, (c) measurement of inside-ZP diameter, combined with morphological selection, is useful to remove non-competent oocytes. Further studies are needed to dissect the developmental capacity of medium and large gilt oocytes. Also, further timelapse studies may reveal a time interval in which the first cleavage of embryos with high developmental capacity takes place. Table 1.Rates of cleavage (CL%), blastocyst (BL%), and total no. of cells (mean ± SEM) in blastocysts of PA embryos from gilts and sows1

59 HIGHER BLASTOCYST FORMATION OF SOMATIC CELL NUCLEAR TRANSFER EMBRYOS DOES NOT GUARANTEE BETTER PREGNANCY IN PIG

2007 ◽  
Vol 19 (1) ◽  
pp. 147
Author(s):  
E. Lee ◽  
K. Song ◽  
Y. Jeong ◽  
S. Hyun
Keyword(s):  
Somatic Cell ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Cell Number ◽  
Skin Fibroblasts ◽  
Miniature Pig ◽  
Donor Cells ◽  
Fetal Fibroblasts

Generally, blastocyst (BL) formation and embryo cell number are used as main parameters to evaluate the viability and quality of in vitro-produced somatic cell nuclear transfer (SCNT) embryos. We investigated whether in vitro development of SCNT pig embryos correlates with in vivo viability after transfer to surrogates. For SCNT, cumulus–oocyte complexes (COCs) were matured in TCM-199 supplemented with follicular fluid, hormones, EGF, cysteine, and insulin for the first 22 h and in a hormone-free medium for 18 h. Three sources of pig skin cells were used as nuclear donor: (1) skin fibroblasts of a cloned piglet that were produced by SCNT of fetal fibroblasts from a Landrace × Yorkshire × Duroc F1 hybrid (LYD), (2) skin fibroblasts of a miniature pig having the human decay accelerating factor gene (hDAF-MP), and (3) skin fibroblasts of a miniature pig with a different strain (MP). MII oocytes were enucleated, subjected to nuclear transfer from a donor cell, electrically fused, and activated 1 h after fusion. SCNT embryos were cultured in a modified NCSU-23 (Park Y et al. 2005 Zygote 13, 269–275) for 6 days or surgically transferred (110–150 fused embryos) into the oviduct of a surrogate that showed standing estrus on the same day as SCNT. Embryos were examined for cleavage and BL formation on Days 2 and 6, respectively (Day 0 = the day of SCNT). BLs were examined for their cell number after staining with Hoechst 33342. Pregnancy was diagnosed by ultrasound 30 and 60 days after embryo transfer. Embryo cleavage was not affected by donor cells (82, 81, and 72% for LYD, hDAF-MP, and MP, respectively), but BL formation was higher (P &lt; 0.05) in hDAF-MP (16%) than in LYD (9%) and MP (6%). MP showed higher (P &lt; 0.05) BL cell number (46 cells/BL) than hDAF-MP (34 cells) but did not show a difference from LYD (37 cells). LYD and MP showed higher pregnancy rates (Table 1) on Days 30 and 60, even though they showed lower BL formation in vitro. Due to a relatively small number of embryo transfers through a limited period, we could not exclude any possible effects by seasonal or operational differences. These results indicated that pregnancy did not correlate with in vitro BL formation of SCNT pig embryos but rather were affected by the source of donor cells. Table 1.In vivo development of somatic cell nuclear transfer pig embryos derived from different sources of donor cells This work was supported by the Research Project on the Production of Bio-organs (No. 200506020601), Ministry of Agriculture and Forestry, Republic of Korea.

40 TRICHOSTATIN A TREATMENT EFFECTS ON IN VITRO DEVELOPMENT OF INTERSPECIES NUCLEAR TRANSFER CAT EMBRYOS DEPEND ON RECIPIENT CYTOPLASM SPECIES

2015 ◽  
Vol 27 (1) ◽  
pp. 113
Author(s):  
L. T. K. Do ◽  
Y. Sato ◽  
M. Taniguchi ◽  
T. Otoi
Keyword(s):  
Nuclear Transfer ◽  
Treatment Effects ◽  
Trichostatin A ◽  
Polar Body ◽  
Blastocyst Stage ◽  
Control Group ◽  
Fluid Medium ◽  
First Polar Body ◽  
Bovine Oocytes

The developmental ability of interspecies somatic cell nuclear transfer (iSCNT) embryos decreases as the taxonomic distance between the donor and recipient species increases. Treatment of cat iSCNT embryos using bovine oocytes with 50 nM of trichostatin A (TSA) improves in vitro embryonic development (Wittayarat et al. 2013 Cell. Reprogram. 15, 301–308). This study investigated whether the TSA treatment effects differ between the development of cat iSCNT embryos reconstructed with porcine and bovine oocytes. Porcine and bovine cumulus-oocyte complexes were in vitro matured for 44 h and 24 h, respectively. After cumulus cell removal, enucleation was performed by aspiration of the metaphase II plate and the first polar body using a piezo-driven pipette. A cat fibroblast cell was then injected into cytoplasm of successfully enucleated oocyte. Reconstructed cybrids were electrically activated by a single 1.5 kV cm–1 pulse for 100 µs (pig-cat embryos), or a 2.3 kV cm–1 pulse for 30 µs (cow-cat embryos). Pig-cat and cow-cat embryos were cultured in porcine zygote medium (PZM)-5 and modified synthetic oviducal fluid medium (mSOF), respectively. After electrical activation, pig-cat and cow-cat embryos were cultured in medium supplemented with 5 µg mL–1 cytochalasin B + 50 nM TSA (TSA group) or without TSA (control group), and the cow-cat embryo medium was also supplemented with 10 µg mL–1 cycloheximide. After 2 h, TSA-treated pig-cat and cow-cat embryos were incubated in medium supplemented with TSA for 22 h, followed by 48 h incubation without TSA. Pig-cat and cow-cat control embryos were cultured in medium without TSA for 70 h after activation. Then, all pig-cat and cow-cat embryos were cultured in porcine blastocyst medium (PBM) or mSOF medium supplemented with 5% fetal bovine serum, respectively, for 5 additional days. Four to seven replicates were performed for each experiment. Data were analysed using Student's t-test. For pig-cat embryos, no difference was observed in cleavage rates between both groups, but development to the blastocyst stage was higher in the pig control group (n = 147, 8.0%) than that of pig TSA group (n = 131, 0.7%; P < 0.05). In contrast, development to the blastocyst stage in cow-cat embryos was not observed in the cow control group (n = 125, 0%), but it was observed in cow TSA group (n = 136, 3.7%). These results indicate that TSA treatment effects are species-specific, but those effects remain to be clarified.

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